Iron cores for rotating electric machines are manufactured by laminating a plurality of sheets of iron core materials stamped from an electrical steel sheet, for example. In this case, deviations arise in the sheet thickness of the iron core materials to be laminated. To accommodate the deviations or skew the iron cores, the iron core materials are stacked by rotary lamination, that is, the stamped iron core materials are laminated while being rotated appropriately.
For example, Patent Literature 1 discloses an apparatus for manufacturing a laminated iron core, including a blanking die for laminating iron core materials stamped from an electrical steel sheet while rotating the materials, a servomotor for generating driving force to rotate the blanking die, and an endless cog belt for transferring the driving force generated by the servomotor to the blanking die. That is, according to the apparatus, the driving force generated by the servomotor is transferred through the belt to the blanking die, and thus the iron core materials are laminated while being rotated appropriately.